For Royal College of Art design students Chris Glaister, Afshin Mehin and Tomas Rosen, the problem with concrete is once you put it down you can't change it, and people have to just get used to it. So they decided to make concrete that changes color and came up with Chronos Chromos Concrete, a system that uses heat conduction to enable the display of patterns in the concrete. Suitable for outdoor and indoor applications, it takes about five seconds to make a color change. They made a short video demonstrating a change, watch it to get a better idea of how the technology works.